Problem- FIN OH Alarm at TRA30C

[parametric.ms]

My QT10 show 25 F Servo Amp Alarm even I didn't move all axis.
I checked the servo amp at backpanel, it shows FIN OH Led lit. I swapped the drive X <-> Z but the alarm still on X Servo amp.
If I remove the servo motor cable (A,B), the alarm dissapear and the amplifier sink temperatur looks quite normal.

What is the real problem? servo motor or anything else?

Thanks
Andre

[onthebumper]

FIN OH is for the colling fins on the back of the drive unit. Are you sure there is no other LED's showing alarm. It sounds strange that when you disconnect the motor from the drive that the alarm goes away because it has nothing to do with the motor.

In any case if you have swapped the drive units and the drive is still alarming out with the same alarm then it shows there is a problem in the drive. Probably there is a bad temperature sensor on the cooling fins in the drive.

[parametric.ms]

let me describe my case one by one
when the 1st time I turn on the machine, about 3-5 min the alarm show up (25 F Servo Amp X)
I checked the drive it show FIN OH Led was lit on X drive. I swapped the drive with Z drive and turn on the machine. but the alarm still on X drive position even I swapped with Z drive. So I turn off the machine, then I remove the servo motor cable for X axis.
After I remove the cable and turn on the machine the alarm didn't appear for over 1 hour.
So what is problem that makes my drive overheat?

[onthebumper]

You can check the motor very easily with ohm meter. Pull the A and B leads off of the drive. Measure each wire to ground on the machine. You should not get less then 10 million ohms. Check the brushes on the motor. Try to remove them and put an air gun in the brush hole to blow out any carbon dust in the motor.